KR20120005479A - Polyurethane dispersion, method of producing the same, coated articles, and method for coating articles - Google Patents

Abstract

The present invention relates to polyurethane dispersions, methods for their preparation, coated articles and methods for coating articles. The polyurethane dispersion according to the invention comprises (a) at least one reaction product comprising the reaction product of at least one natural oil-based polyol and at least one isocyanate dissolved in dipropylene glycol dimethyl ether in the presence of at least one first surfactant. One or more polyurethane units derived from the prepolymer and (b) water.

Description

POLYURETHANE DISPERSION, METHOD OF PRODUCING THE SAME, COATED ARTICLES, AND METHOD FOR COATING ARTICLES}

Cross Reference to Related Application

The application is filed on March 31, 2009 and is entitled "Polyurethane Dispersion, Process for Making It, Coated Articles and Coating Methods of Articles (POLYURETHANE DISPERSION, METHOD OF PRODUCING THE SAME, COATED ARTICLES, AND METHOD FOR COATING) ARTICLES), a formal application claiming priority from US Provisional Patent Application 61 / 165,013, the teachings of which provisions are incorporated herein by reference as if fully reproduced herein.

Field of invention

The present invention relates to polyurethane dispersions, methods for their preparation, coated articles and methods for coating articles.

Adhesion is an important performance characteristic for surface coating applications such as wood coating, concrete coating, metal coating or plastic coating. Polyurethane dispersions are commonly used in these coatings, either by the order of production or by subsequent individual end users. Due to the nature of the wood surface and polyurethane chemistry, adhesion to the wood surface is very difficult. Several different approaches have been adopted to promote better adhesion to wood substrates. These approaches are more like, for example, the introduction of silane functional groups onto the polyurethane backbone, acrylic / vinyl functional groups such as hybrids and blends, the introduction of fatty acid modifications into the backbone, ultraviolet curing moieties as well as fluorination and chlorination. Includes the introduction of exotic chemistry. It is also common to use adhesion promoters as additives to promote adhesion. However, this approach incurs additional costs and efforts to achieve the desired performance.

Accordingly, there is a need for polyurethane dispersions that provide improved adhesion to, for example, wood coatings, concrete coatings, metal coatings or plastic coatings. There is also a need for a process for the preparation of polyurethane dispersions which provides improved adhesion, for example in the field of wood coatings, concrete coatings, metal coatings or plastic coatings.

Summary of the Invention

The present invention relates to polyurethane dispersions, methods for their preparation, coated articles and methods for coating articles.

In one embodiment, the invention comprises (a) at least one reaction product comprising a reaction product of at least one natural oil-based polyol and at least one isocyanate dissolved in dipropylene glycol dimethyl ether in the presence of at least one first surfactant Provided are polyurethane dispersions comprising at least one polyurethane unit derived from at least one prepolymer, and (b) water.

In another embodiment, the present invention comprises (1) a reaction product of at least one natural oil-based polyol and at least one isocyanate dissolved in dipropylene glycol dimethyl ether in the presence of at least one surfactant and optionally at least one Providing a first stream comprising at least one prepolymer neutralized with at least one neutralizing agent, (2) providing a second stream comprising water, (3) joining the first stream and the second stream together Step (4) thereby forming a prepolymer dispersion, (5) optionally neutralizing the prepolymer dispersion, (6) chain extending the prepolymer, (7) thereby forming a polyurethane dispersion It provides a method of producing a polyurethane dispersion, comprising the step of.

In another embodiment, the present invention includes a substrate and a coating associated with at least one surface of the substrate, wherein the coating is (a) at least one natural oil dissolved in dipropylene glycol dimethyl ether in the presence of at least one surfactant. Provided is a coated article derived from a polyurethane dispersion comprising at least one polyurethane unit derived from at least one prepolymer comprising a reaction product of a systemic polyol and at least one isocyanate, and (b) water.

In another embodiment, the present invention provides a process for preparing a substrate comprising (1) selecting a substrate, (2) (a) at least one natural oil-based polyol and at least one dissolved in dipropylene glycol dimethyl ether in the presence of at least one surfactant Selecting a coating composition comprising at least one polyurethane unit derived from at least one prepolymer comprising a reaction product of isocyanate, and (b) a polyurethane dispersion comprising water, (3) at least one of the substrates Applying a coating composition to a surface, (4) removing at least a portion of water, and (5) forming a coated article thereby.

In an alternative embodiment, the present invention relates to the invention wherein at least one prepolymer is at least one natural oil-based polyol and at least one isocyanate dissolved in dipropylene glycol dimethyl ether and dipropylene glycol dimethyl ether in the presence of at least one surfactant. Except for including the reaction product of the present invention, there is provided a polyurethane dispersion according to any preceding embodiment, a method for preparing the same, a coated article, and a method for coating the article.

For the purpose of illustrating the invention, it is to be understood that the exemplary forms are shown in the drawings, but the invention is not limited to the precise arrangements and means shown.
1 shows a first embodiment of soy monomer chemistry.
2 is a graph depicting shear stress as a function of time, monitoring early hardness development.

The present invention is a polyurethane dispersion, a method for preparing the same, a coated article and a method for coating the article. The polyurethane dispersion according to the invention comprises (a) at least one reaction product comprising the reaction product of at least one natural oil-based polyol and at least one isocyanate dissolved in dipropylene glycol dimethyl ether in the presence of at least one first surfactant. One or more polyurethane units derived from the prepolymer, and (b) water. The method for producing a polyurethane dispersion according to the invention comprises (1) a reaction product of at least one natural oil-based polyol and at least one isocyanate dissolved in dipropylene glycol dimethyl ether in the presence of at least one first surfactant and optionally Providing a first stream comprising at least one prepolymer neutralized with at least one neutralizing agent, (2) providing a second stream comprising water, (3) providing a first stream and a second stream; Joining together, (4) thereby forming a prepolymer dispersion, (5) optionally neutralizing the prepolymer dispersion, (6) chain extending the prepolymer, (7) thereby polyurethane Forming a dispersion.

The average particle size diameter of the solids of the polyurethane dispersion of the invention is in the range of 50 to 1000 nm, for example the average particle size diameter is 50 to 500 nm, or alternatively 50 to 500 nm, or alternatively 50 to 150 nm, or alternatively 60 to 100 nm, or alternatively 60 to 80 nm. The polyurethane dispersions of the present invention may have a solids content in the range of 20 to 60% by weight without including any additional filler weight, for example a solids content of 30 to 50% by weight, or alternatively 20 to 50% by weight, or alternatively in the range of 30 to 40% by weight. The polyurethane dispersions of the present invention have a viscosity in the range of 100 to 3000 cPs at 25 ° C., for example 100 to 1000 cPs at 25 ° C., or alternatively 200 to 900 cPs at 25 ° C., or alternatively 200 to 600 cPs at 25 ° C. Have The polyurethane dispersions of the present invention may comprise 0 to 30, or 5 to 25, or 5 to 20, or 0 to 20% by weight of one or more solvents.

The polyurethane dispersions according to the invention comprise at least one filler, at least one crosslinking agent, at least one antifoaming agent, at least one pigment or colorant, at least one rheology modifier, at least one adhesion promoter, at least one damage resistance and lubricant. (mar and slip agent), one or more wetting agents, one or more antifreeze agents, one or more biocides or antimicrobials, one or more surfactants, one or more UV stabilizers, one or more antioxidants, one or more flows Modulators, and combinations thereof.

The at least one prepolymer comprises a reaction product of at least one isocyanate with a mixture dissolved in dipropylene glycol dimethyl ether in the presence of at least one first surfactant, the mixture comprising at least one natural oil-based polyol and at least one Adipate polyols, and optionally one or more short diols.

natural Oil Polyol

Natural oil-based polyols are polyols based on or derived from renewable feedstocks, such as plant seed oils and / or animal fats of natural and / or genetically modified plants. Such oils and / or fats are generally composed of triglycerides, ie fatty acids linked together with glycerol. Preference is given to vegetable oils having at least about 70% unsaturated fatty acids in the triglycerides. The natural product may contain at least about 85% by weight of unsaturated fatty acids. Examples of preferred vegetable oils are, for example, castor oil, soybean oil, olive oil, peanut oil, rapeseed oil, corn oil, sesame oil, cottonseed oil, canola oil, safflower oil, linseed oil, palm oil, grapeseed oil, black caraway oil , Pumpkin kernel kernel oil, borage seed oil, wood germ oil, apricot kernel oil, pistachio oil, almond oil, macadamia nut oil, avocado oil, mountain bark oil, hemp oil , Hazelnut oil, evening primrose oil, wild rose oil, thistle oil, walnut oil, sunflower oil, jatropha seed oil, or combinations thereof. In addition, oils obtained from organisms such as algae may also be used. Examples of animal products include lard, bee tallow, fish oil and mixtures thereof. Combinations of vegetable and animal oils / fats may also be used.

Several chemistries can be used to make natural oil based polyols. Such modifications of renewable resources include, but are not limited to, for example, epoxidation, hydroxylation, ozonation, esterification, hydroformylation, or alkoxylation. Such modifications are commonly known in the art.

After preparation of such polyols by modification of natural oils, the modified product can be further alkoxylated. The use of ethylene oxide (EO) or a mixture of EO and other oxides introduces hydrophilic residues into the polyol. In one embodiment, the modified product is alkoxylated with EO sufficient to produce a natural oil based polyol having from 10 wt% to 60 wt% EO, eg, 20 wt% to about 40 wt% EO.

In other embodiments, natural oil-based polyols are obtained through a multi-step process such as undergoing transesterification of animal or vegetable oils / fats and recovering constituent fatty acids. After this step, the carbon-carbon double bonds of the constituent fatty acids are hydroformylated to form hydroxymethyl groups, which are then formed by the reaction of the hydroxymethylated fatty acids with the appropriate initiator compound to form a polyester or polyether / polyester. . Such multi-step processes are commonly known in the art and are described, for example, in PCT publications WO 2004/096882 and WO 2004/096883. Multistage processes produce polyols having both hydrophobic and hydrophilic residues, which result in improved miscibility with both water and conventional petroleum based polyols.

The initiator for use in the multistage process for the production of natural oil-based polyols can be any initiator used in the production of conventional petroleum-based polyols. The initiators are, for example, neopentyl glycol, 1,2-propylene glycol, trimethylolpropane, pentaerythritol, sorbitol, sucrose, glycerol, diethanolamine, alkanediols, for example 1,6-hexanediol, 1,4-butanediol, 1,4-cyclohexane diol, 2,5-hexanediol, ethylene glycol, diethylene glycol, triethylene glycol, bis-3-aminopropyl methylamine, ethylene diamine, diethylene triamine, 9 (1) -hydroxymethyloctadecanol, 1,4-bishydroxymethylcyclohexane, 8,8-bis (hydroxymethyl) tricyclo [5,2,1,0 ^2,6 ] decene, dimerol Alcohols (36 diols available from Henkel Corporation), hydrogenated bisphenols, 9,9 (10,10) -bishydroxymethyloctadecanol, 1,2,6-hexanetriol and combinations thereof It may be selected from the group consisting of. Alternatively, the initiator is present internally in glycerol, ethylene glycol, 1,2-propylene glycol, trimethylolpropane, ethylene diamine, pentaerythritol, diethylene triamine, sorbitol, sucrose, or any of those described above. At least one of the alcohol or amine groups can be selected from the group consisting of reacted with ethylene oxide, propylene oxide or mixtures thereof and combinations thereof. Alternatively, the initiator is glycerol, trimethylolpropane, pentaerythritol, sucrose, sorbitol, and / or mixtures thereof.

In one embodiment, the initiator is alkoxylated with ethylene oxide, or a mixture of ethylene oxide and at least one other alkylene oxide, such that it is alkoxylated with a molecular weight of about 200 to about 6000, preferably about 500 to about 3000. It becomes an initiator.

The functionality of at least one natural oil-based polyol is greater than about 1.5 and generally no greater than about 6. In one embodiment, the functionality is less than about 4. In one embodiment, the functionality is in the range of 1.5 to 3. The hydroxyl number of the at least one natural oil based polyol is less than about 150 mg KOH / g, preferably about 50 to about 120, more preferably about 60 to about 120. In one embodiment, the hydroxyl number is less than about 100.

The level of renewable feedstock in natural oil-based polyols may vary from about 10 to about 100%, generally from about 10 to about 90%.

Natural oil-based polyols may comprise up to about 90% by weight of the polyol blend. However, in one embodiment, the natural oil based polyol is at least 5%, at least 10%, at least 25%, at least 35%, at least 40%, at least 50%, or at least 50% by weight of the total weight of the polyol blend, or At least 55 weight percent. Natural oil-based polyols may comprise at least 40%, at least 50%, at least 60%, at least 75%, at least 85%, at least 90%, or at least 95% by weight of the total weight of the combined polyols. Can be. Combinations of two or more natural oil-based polyols may also be used.

The viscosity of the natural oil based polyols measured at 25 ° C. is generally less than about 6000 mPa · s, for example the viscosity of the natural oil based polyols measured at 25 ° C. is less than about 5000 mPa · s. Natural oil-based polyols may have a molecular weight in the range of 500 to 3000 daltons, for example 800 to 1500 daltons. NOPs include aliphatic and aromatic polyester polyols including caprolactone polyester polyols, optional polyester / polyether hybrid polyols, and PTMEG-based polyether polyols; Polyether polyols based on ethylene oxide, propylene oxide, butylene oxide and mixtures thereof; Polycarbonate polyols; Polyacetal polyols, polyacrylate polyols; Polyesteramide polyols; Polythioether polyols; It can be a blend with any of polyolefin polyols, such as saturated or unsaturated polybutadiene polyols.

Isocyanate:

Examples of polyisocyanate compounds include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2 , 4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, 3,3'-dimethyl-4,4'-biphenylene diisocyanate, 3,3'-dimethoxy-4,4 '-Biphenylene diisocyanate, 3,3'-dichloro-4,4'-biphenylene diisocyanate, 1,5-naphthalene diisocyanate, 1,5-tetrahydronaphthalene diisocyanate, tetramethylene diisocyanate, 1 , 6-hexamethylene diisocyanate, dodecamethylene diisocyanate, trimethylhexamethylene diisocyanate, 1,3 and 1,4-bis (isocyanatemethyl) isocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, hydrogenationSilylene diisocyanate, lysine diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 3,3'-dimethyl-4,4'-dicyclohexylmethane diisocyanate, isomers thereof and // Or combinations thereof.

First surfactant

It may comprise less than 6% by weight of the first surfactant, for example, may comprise 4 to 6% by weight of the first surfactant. Exemplary first surfactants include, but are not limited to, dimethylol propionic acid, dimethylol propionic acid, dimethylol botanic acid, and diaminosulfonate.

menstruum

The solvent can be any solvent, for example the solvent can be an organic solvent. Exemplary solvents include, but are not limited to, dipropylene glycol dimethyl ether and tripropylene glycol dimethyl ether commercially available under the trade name PROGLYDE ^® DMM from The Dow Chemical Company. Additional solvents may include acetone, methyl ethyl ketone, toluene and tetrahydrofuran (THF).

Additional solvents include, but are not limited to, propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, propylene glycol diacetate, dipropylene glycol dimethyl ether, diethylene glycol n-butyl ether acetate, ethylene glycol n-butyl ether acetate It is not limited.

Prepolymers:

The at least one prepolymer comprises the reaction product of at least one natural oil-based polyol and at least one isocyanate dissolved in dipropylene glycol dimethyl ether in the presence of at least one first surfactant. The polyurethane prepolymers used in the present invention are prepared by any conventionally known process, such as solution processes, hot melt processes, or polyurethane prepolymer mixing processes, for example in batch or continuous processes. Can be. In addition, polyurethane prepolymers can be prepared, for example, by the process of reacting a polyisocyanate compound with an active hydrogen-containing compound, i.e., at least one natural oil-based polyol, an example of which is that And after the reaction with at least one natural oil-based polyol, optionally removing the solvent. In one embodiment, the at least one prepolymer comprises the reaction product of at least one natural oil-based polyol and at least one isocyanate dissolved in dipropylene glycol dimethyl ether in the presence of at least one first surfactant. In one embodiment, the prepolymer does not contain N-methyl pyrrolidone (NMP).

For example, the polyisocyanate compound may be, for example, at a temperature ranging from about 20 ° C. to about 150 ° C., alternatively from 30 ° C. to 130 ° C., for example from 1.1: 1 to 3: 1, or alternatively from 1.2: 1 to 2: 2. The equivalent ratio of isocyanate groups to active hydrogen groups of 1 can be reacted with at least one natural oil-based polyol dissolved in an organic solvent. Alternatively, the prepolymer can be prepared with an excess of active hydrogen groups to facilitate the preparation of hydroxyl terminated polymers.

Polyurethane prepolymers derived from one or more natural oil-based polyols in organic solvents may be prepared in the presence of one or more reactive or non-reactive ethylenically unsaturated monomers. Such monomers may be further polymerized to prepare a hybrid polyurethane dispersion.

The polyurethane prepolymer may further comprise one or more ionic groups. Functional moieties used to prepare such prepolymers having ionic groups include sulfonic acid diols such as 3- (2,3-dihydroxypropoxy) -1-propane-sulfonic acid; Sulfopolycarboxylic acids such as sulfoisophthalic acid, sulfosuccinic acid; And aminosulfonic acids such as 2-aminoethanesulfonic acid and 3-aminopropanesulfonic acid; Sulfamic acid diols such as N, N-bis (2-hydroxyalkyl) sulfamic acid (C1 to C6 of alkyl groups), or alkylene oxide (AO) adducts thereof, such as ethylene oxide and propylene oxide, N , N-bis (2-hydroxy-ethyl) sulfamic acid; Bis (2-hydroxyethyl) phosphate; Dialkylol alkanoic acids C6 to C24, for example 2,2-dimethylol propionic acid, 2,2-dimethylol butanoic acid, 2,2-dimethylol heptanoic acid, 2,2-dimethylol octanoic acid; And amino acids such as 2-aminoethanoic acid; And salts thereof, such as salts of amines such as triethylamine, alkanolamine, morpholine and / or alkali metal salts such as sodium salts. Examples containing cationic groups include, but are not limited to, quaternary ammonium base-containing diols, tertiary ammonium group-containing diols and salts thereof.

The polyurethane prepolymer may further comprise hydrophilic groups. The term "hydrophilic group" as used herein refers to anionic groups (eg carboxyl groups, sulfonic acid groups, or phosphoric acid groups), or cationic groups (eg tertiary amino groups, or quaternary amino groups), or nonionics. It refers to a hydrophilic group (for example, a group consisting of repeating units of ethylene oxide, or a group consisting of repeating units of ethylene oxide and another repeating unit of another alkylene oxide).

Among hydrophilic groups, polyurethane emulsions, for example, in which a nonionic hydrophilic group having repeating units of ethylene oxide are finally obtained, may be preferable because they have excellent compatibility with other types of emulsions. The introduction of carboxyl and / or sulfonic acid groups is effective to make the particle size finer.

When the ionic group is an anionic group, the neutralizing agents used for neutralization are for example non-volatile bases such as sodium hydroxide and potassium hydroxide; And volatile bases such as tertiary amines (eg trimethylamine, triethylamine, dimethylethanolamine, methyldiethanolamine, and triethanolamine), and ammonia can be used.

When the ionic group is a cationic group, usable neutralizing agents are for example inorganic acids such as hydrochloric acid, sulfuric acid and nitric acid; And organic acids such as formic acid and acetic acid.

Neutralization can be carried out before, during or after the polymerization of the polyurethane prepolymer with ionic groups. Neutralization can be achieved by adding the neutralizing agent directly to the polyurethane prepolymer or by adding it to an aqueous phase during the preparation of the polyurethane dispersion.

The polyurethane prepolymer is further chain extended through the chain extender. Any chain extender known to be useful to those of ordinary skill in the art of making polyurethanes may be used in the present invention. Such chain extenders typically have a molecular weight of about 30 to about 500 and have at least two active hydrogen containing groups. Polyamines are a preferred class of chain extenders. Other substances, especially water, are capable of extending chain length and are therefore chain extenders for the purposes of the present invention. The chain extender is water or an amine such as an aminated polypropylene glycol such as Jeffamine D-400 from Huntsman Chemical Company, amino ethyl piperazine, 2-methyl piperazine, 1,5-diamino-3-methyl-pentane, isophorone diamine, ethylene diamine, diethylene triamine, triethylene tetramine, triethylene pentamine, ethanol amine, lysine in any stereoisomeric form or salt form, hexane Particular preference is given to mixtures of diamine, hydrazine and piperazine with water. In the practice of the present invention, the chain extender may be used as the chain extender aqueous solution.

Polyurethane dispersions ( PUD ) Produce

PUDs according to the present invention can be produced through a batch process or a continuous process. The polyurethane prepolymer, optionally one or more surfactants and water, is fed to a mixer such as an OAKS Mixer or IKA Mixer to disperse the polyurethane prepolymer in water and then Or chain extension with a secondary amine to form a PUD. In one embodiment, the PUD does not contain N-methyl pyrrolidone (NMP).

In one embodiment, the process for preparing the polyurethane dispersion according to the invention comprises (1) at least one natural oil-based polyol and at least one dissolved in dipropylene glycol dimethyl ether in the presence of at least one first surfactant. Providing a first stream comprising at least one prepolymer comprising a reaction product of at least one isocyanate and optionally neutralized with at least one neutralizing agent, (2) providing a second stream comprising water, (3 ) Joining the first and second streams together, (4) thereby forming a prepolymer dispersion, (5) neutralizing the prepolymer dispersion, and (6) chain extending the prepolymer. Step, (7) thereby forming a polyurethane dispersion.

End use purpose

Coated articles according to the invention include a substrate and a coating that is associated with one or more surfaces of the substrate and that is derived from the polyurethane dispersion of the invention as detailed herein above. One or more surfaces of the substrate may be treated, for example primed, before application of the polyurethane dispersion of the present invention. The substrate can be any substrate, for example the substrate can comprise wood, concrete, plastic, metal and combinations thereof.

In one embodiment, the coated article comprises a substrate and a coating associated with one or more surfaces of the substrate, the coating comprising (a) one or more dissolved in dipropylene glycol dimethyl ether in the presence of one or more surfactants At least one polyurethane unit derived from at least one prepolymer comprising a reaction product of a natural oil-based polyol and at least one isocyanate, and (b) a polyurethane dispersion comprising water.

In another embodiment, a method of making a coated article comprises (1) selecting a substrate, (2) (a) at least one natural oil based polyol dissolved in dipropylene glycol dimethyl ether in the presence of at least one surfactant. Selecting a coating composition comprising at least one polyurethane unit derived from at least one prepolymer comprising a reaction product of at least one isocyanate, and (b) a polyurethane dispersion comprising water, (3) said Applying the coating composition to one or more surfaces of the substrate, (4) removing at least a portion of the water, and (5) forming a coated article thereby.

The polyurethane dispersions of the present invention may be applied to one or more surfaces of the substrate, for example, by any method such as spraying, brushing, soaking, drawdowns, and the like.

The polyurethane dispersion of the present invention is a film forming composition. The film derived from the polyurethane dispersion of the present invention is 1 to 2 mm, or alternatively 1 to 500 m, or alternatively 1 to 200 m, or alternatively 1 to 100 m, or alternatively 20 to It may have a thickness in the range of 50 μm. Films derived from the polyurethane dispersions of the invention have a residual ratio of greater than 30%, alternatively greater than 40%, alternatively greater than 50%, alternatively as measured according to ASTM D-3359. May have an adhesion in the residual rate range of greater than 60%. The polyurethane dispersion of the present invention has a hardness development rate in the range of at least 0.002 MPa / min, or alternatively in the range of at least 0.003 MPa / min, or alternatively in the range of at least 0.004 MPa / min, or alternatively in the range of at least 0.005 MPa / min. It can have

After such dispersions have been prepared, additional solvents may be added to the polyurethane dispersions of the present invention. Such solvents include propylene glycol methyl ether, dipropylene glycol methyl ether, tri-propylene glycol methyl ether, propylene glycol n-propylene ether, dipropylene glycol n-propyl ether, tri-propylene glycol n-propyl ether, propylene glycol n- Phenyl ether, diethylene glycol ethyl ether, diethylene glycol methyl ether, diethylene glycol n-butyl ether, diethylene glycol hexyl ether, ethylene glycol propyl ether, ethylene glycol n-butyl ether, ethylene glycol hexyl ether, triethylene glycol methyl Ethers, triethylene glycol ethyl ether, triethylene glycol propyl ether, ethylene glycol n-butyl ether, ethylene glycol phenyl ether, ethylene glycol n-butyl ether mixtures, and mixtures of these solvents.

End use applications include, but are not limited to, industrial and architectural coatings on any substrate, such as wood, concrete, plastic, metal, and combinations thereof. Such end use applications include, but are not limited to, furniture, floors, kitchen cabinets, and the like.

Example

The following examples illustrate the invention but are not intended to limit the scope of the invention.

NOP Polyol  synthesis

Natural oil polyols (NOP) were prepared in three reaction steps from fatty acid methyl esters (FAMES) derived from soybean oil. As shown in FIG. 1, the FAMES is first hydroformylated with an aldehyde intermediate and then hydrogenated with soy monomer in a second step. The average hydroxyl functionality of the soy monomer is approximately 1.0.

The resulting monomer is then transesterified with the appropriate glycol. In this method, the polyol molecular weight is increased by the condensation of the monomer with the glycol initiator and the self condensation of the monomer. By controlling the average functionality of the monomers and the ratio of monomers to the glycol initiator, both the polyol molecular weight and the average functionality can be controlled systematically. In addition, the structure of the initiator can be adjusted to achieve the desired performance characteristics and compatibility. Preferred glycol initiators contain reactive primary hydroxyl groups such as 1,6-hexanediol and UNOXOL ™ diols. UNOXOL ™ diols are liquid cycloaliphatic diols that are approximately 50:50 mixtures of 1,3-cyclohexanedimethanol and 1,4-cyclohexanedimethanol (mixture of cis and trans isomers).

Prepolymer Manufacturing Method

Preparation of the prepolymer was carried out in a 500 ml four neck round bottom flask equipped with an addition device, a water cooled condenser, a mechanical stirrer, a thermometer and a nitrogen inlet / outlet tube. During the entire reaction step, a nitrogen purge and a stirring rate of 500 rpm were applied. The reaction temperature was maintained using an oil bath as the heating source. In conventional prepolymer preparation, polyester polyol and dimethylolpropionic acid [DMPA] were added to the reaction flask followed by the isocyanate. The polyols added individually or as a blend were initially heated to a temperature below 15-20 ° C. below the desired reaction temperature. After completion of the polyol and solvent addition, the reaction mixture was heated with stirring (200 rpm) to the desired temperature (80-90 ° C.). Once the theoretical% NCO was reached, the final product was delivered to a sample container with a nitrogen blanket and used for the dispersion. Suitable solvents for the prepolymer include dimethyl ether of acetone, methyl ethyl ketone and dipropylene glycol.

Polyurethane dispersions ( PUD ) synthesis

The PUD may be subjected to a small (500 mL) batch process in which the prepolymer is neutralized with 95 to 110% stoichiometric amounts (moles) of tertiary amines (eg triethyl amine, TEA) of the acid used in the prepolymer. Prepared. The desired amount of water was slowly added to the prepolymer with vigorous mixing using a special mixer that generated high shear (50,000 to 100,000 sec ⁻¹ ). As water was added continuously, the dispersion viscosity dropped below ˜3000 cP (Brookfield Spindle # 4, 50 rpm). The dispersion was then completely extended with amine (eg ethylene diamine). The final dispersion had ˜35 wt% solids content and ˜100 nm number average particle size.

Of the present invention Example  One:

NOP in PROGLYDE ^® DMM solvent. The raw materials of the formulations shown in Table 1 were used to prepare the PUD of Example 1 of the present invention containing 100 gm of prepolymer.

The composition was used to obtain the desired PUD according to the procedure described in the previous section. PUDs were analyzed for percent solids and particle size and then coated on different substrates. The coating was applied to a pre-sealed oak wood substrate using a paint brush. Before testing the properties, samples were dried for 7 days under ambient conditions (50% RH and 23 ° C.).

Comparative example  2 manufacturing

The composition used in Example 1 was modified by replacing PROGLYDE ^® DMM with N-methyl pyrrolidone [NMP] as the solvent.

Comparative example  3 manufacturing

The composition used in Example 1 was modified by replacing the NOP polyol with caprolactone diols of similar molecular weight and functionality. PROGLYDE ^® DMM was used as solvent.

Comparative example  4 manufacturing

The composition used in Example 1 was modified by replacing the NOP polyol with a similar molecular weight and functionality of the FomRez PES-G24-112 polyol provided from Chemtrua. PROGLYDE ^® DMM was used as solvent.

Coating sample manufacturers

The coating was applied to the presealed oak wood substrate using a paint brush. Before testing the properties, samples were dried for 7 days under ambient conditions (50% RH and 23 ° C.).

Adhesion measurements were performed according to ASTM D-3359. A coating was formed on the oak tree and dried for 7 days under ambient conditions before testing. Adhesiveness was tested by using a cross-hatch tool to create a lattice scratch leaving 100 square marks with a side dimension of 1 mm. Scotch tape from 3M with a peel strength of 60 N / m 2 was used to test the adhesion. One piece of tape was cut and placed on top of the reticulated wire, and pressed using an eraser to obtain a uniform contact. The tape was pulled at 180 degrees within 90 seconds of attaching the tape. The number of squares where the coating was damaged or removed was recorded and the percentage remaining was used as a parameter to measure adhesion. Table 2 summarizes these results.

Early hardness manifestations:

Hardness expression was monitored by measuring modulus over time using dynamic mechanical spectroscopy. Measurements were made in shear mode using strained parallel plate geometry. The aqueous PUD was placed in an aluminum cup having a 25 mm diameter and pressed to a film thickness of 1 mm by a plate attached to the measurement load cell. Vibration shear measurements were performed at 1 Hz with varying percent strain based on cure range. The test was performed at 23 ° C. and 50% RH. Data points were collected every 10 minutes for a 24 hour period. Adipate PUD made from the polyols, as well as in comparison to its competitors PUD, faster more soy polyol, and a hardness expressed in the case of using a combination of PROGLYDE ^® DMM solvent. The result is shown in FIG. The y axis represents the shear stress measured every 10 minutes at a frequency of 1 Hz and strain in the linear region. There may be a change in onset depending on the amount of water in the PUD. The velocity or slope of the line represents the rate of hardness development, and it can be clearly seen that soybean PUD using PROGLYDE DMM shows a rapid rate of early hardness.

Additional Example

Sample A

48.5 g (800 MW, 0.12 equiv) natural oil polyester polyol (NOP), 4 g (144 MW, 0.06 equiv) 50 / of UNOXOL diol, 1,3 cyclohexane dimethanol and 1,4 cyclohexane-dimethanol isomer 50 mixture, 5 g (134 MW, 0.07 equiv) dimethylolpropionic acid (DMPA), 25 g PROGLYDE ^® DMM solvent (dipropylene glycol dimethyl ether), 0.01 g dibutyltin dilaurate (DBDTL) catalyst It was added to a reaction vessel with a jacket equipped with a stirrer, a heater, a thermocouple and a condenser and heated to 80 ° C. while stirring under a nitrogen head. 42.5 g (222 MW, 0.38 equiv) of isophorone diisocyanate (IPDI) was added to the reaction mixture (initial isocyanate for hydroxyl content: 1.5 equiv / equiv) and held at 80 ° C. for 4 hours, 5.5 wt% A urethane prepolymer having an NCO content of was formed. The reaction mixture was cooled to 60 ° C. and 3.8 g (101 MW, 0.04 equiv) of triethylamine (TEA) were added with stirring to neutralize the COOH group (0.04 equiv) of DMPA (carboxyl to amine content: 1 equiv / equiv). 140 g of water were added with mixing to form a dispersion of anionic stabilized prepolymer in water. A 10 g solution of 41 g of cooled ethylene diamine (EDA, 60 MW, 0.14 equiv) in water was added with stirring for the chain extension step to form a urea linkage with the remaining NCO groups (isocyanate to amine content). 0.96 equiv / equiv). The polyurethane dispersion (PUD) was cooled to room temperature and the following properties were measured.

ㆍ Appearance: translucent dispersion, dried with transparent film

PH: 8 to 10

Density: 1.1 g / cc at 25 ° C

Viscosity: 500 cP at 25 ° C

Average particle size: 120 nm

Solid content: 34 wt%

Minimum film formation temperature: <0 ° C

Sample B

Use the same formulation and procedure as sample A, with the only changes that performed the neutralization (using TEA), chain extension (using EDA), and dispersion steps with a rotor stator mechanical disperser rather than a batch mixer. Sample B was prepared. The properties of Sample B were essentially similar to Sample A.

Sample C

Sample C was prepared using the same procedure as sample A, but changing the polyol composition as follows: 48.5 g (800 MW, 0.12 equiv) natural oil polyester polyol and 4 g (144 MW, 0.06 equiv) UNOXOL diol, 22 g (0.06 equiv) natural oil polyester polyol, 6 g (0.08 equiv) UNOXOL diol and 22 g UNOXOL adipate (884 MW, 0.05 equiv) were replaced. The NCO / OH ratio before the reaction did not change at 1.5. The PUD physical properties of Sample C were essentially similar to Sample A. Compared to the film from Sample A, the film from Sample C was harder and better wear resistant because of the higher levels of short chain diols and higher Tg polyester polyols that contribute to the hard segment content of the polymer.

Sample D

Sample D was prepared using the same formulation and procedure as Sample A, but replacing the solvent type with 25 g n-methyl pyrrolidone in 25 g PROGLYDE DMM. The properties of Sample D were essentially similar to Sample A.

Sample E

Sample E is a high solid aliphatic PUD (R-4188) commercially available from Essential Industries, which contains 9% NMP solvent for use as a sealer or topcoat of a stone substrate. PUD characteristics are as follows.

ㆍ Appearance: Translucent

PH: 7.6

Solid content: 38 wt%

Viscosity: 50 cP at 25 ° C

Density: 1.05 g / cc at 25 ° C

Sample F

Sample F is a solventless aliphatic urethane acrylic hybrid (R-4388) from Essential Industries for concrete topcoat applications. The characteristics are as follows.

ㆍ Appearance: Translucent

PH: 7.7

Solid content: 41 wt%

Viscosity: <300 cP at 25 ° C

Density: 1.05 g / cc at 25 ° C

PUD  film Performance test :

Film performance tests were performed by diluting all PUD samples to 30 weight percent solids to achieve the same film formation. Samples A, B, C, and D all formed good, uniform, flawless films without the need for cosolvents, while Sample E (9% NMP) and Sample F (0% NMP) produced good, defect free films. Additional 5% NMP was needed to form.

Adhesion test

Adhesion tests were performed according to ASTM D 3359. This test evaluates the adhesion of the coated film to the untreated and undercoated substrate by making a lattice pattern cut comprising 1/8 "reticulated lines on the film and applying a pressure sensitive tape over the lined area. The amount of the raised or removed coating is measured by peeling off the tape and counting the remaining reticular squares In a multicoat system, it is important to measure the adhesion failure between coatings or between coating and substrate. primer) or a coating having good adhesion to the substrate exhibits a value of> 80%, preferably> 90%, even more preferably> 95% coating residual percentage, for the tape pull test.

Concrete test block

An acrylic epoxy emulsion (Quikrete 02-51730 garage floor sealer) was coated on a concrete test block (Patio Concrete Products Inc.) made according to ASTM specifications and air dried at room temperature for a week. . Then, samples A to F were coated on the undercast concrete blocks. The experimental results for the various samples are described in Table 1A, and the contents are as follows.

In both untreated and low levels of external crosslinker (aziridine) treatment, the NOP PUD samples A and B of the present invention containing PROGLYDE DMM solvent showed very good adhesion. In contrast, in both untreated and low levels of external crosslinker (aziridine) treatment, NOP PUD comparative sample D, made of the same formulation and containing NMP, showed very poor and unacceptable adhesion. This comparative sample will require an adhesion promoter in the formulation or a tie layer upon application to overcome this drawback.

In both untreated and low levels of external crosslinker (aziridine) treatment, the NOP PUD Sample C of the present invention containing PROGLYDE DMM solvent is very good when compared to the NOP PUD Comparative Sample D made from the same level of NMP solvent. Adhesiveness was shown. The formulations were similar except for the levels of polyester polyols (NOP, UNOXOL adipate) and short chain diols (UNOXOL).

Commercial PUD and WB urethane acrylic control samples E and F, made with 9% and 0% NMP solvents and made with 5% additional NMP solvent for good film formation, are very scarce and unacceptable in untreated form. Adhesiveness was shown. In addition, sample F tested at low levels of external crosslinker (aziridine) showed very poor and unacceptable adhesion. These control samples will need an adhesion promoter in the formulation or a connection layer in application to overcome adhesion defects.

[Table 1A]

Dust pollution tolerance Dirt Pick - up Resistance  ) exam

Dust contamination resistance was measured by Chinese national standard method. The coating was applied to a white plastic panel, dried for 7 days at room temperature, and the initial Y reflectance measured at three locations using a BYK Gardner Calorimeter Model 6805. The charcoal used as a representative dust medium is mixed 1: 1 with water and 0.7 g is uniformly applied to a white coated plastic panel using a soft brush as a paste and dried at 23 ° C., 50% RH for 2 hours. . A shower is simulated by placing the panel in a sample rack of drainage and rinsing with a sprinkler connected to the faucet for 1 minute. Move all positions of the panel to rinse under running water. The panel is dried at 23 ° C., 50% RH for 24 hours and the cycle is repeated a total of 5 cycles. The final Y reflectance of the panel is measured at the same location and the average change in reflectance (ΔY) is calculated.

Change in Y Reflectance = ΔY = 100 * (Initial Y Reflectance-Final Y Reflectance) / Initial Y Reflectance

Coatings with good dust contamination resistance exhibit a change in reflectance value ΔY of 5 or less, preferably 10 or less, more preferably 5 or less, after 5 cycles of carbon material exposure and cleaning.

The actual experimental test results are shown in Table 2A, and the contents are as follows.

The NOP PUD samples of the present invention (Samples A, B, C) made with PROGLYDE DMM solvent showed very low ΔY values for the DPR test when untreated and showed low ΔY values when tested with aziridine crosslinker. . Visually, the rate of change of white in the coated sample was minimal after 5 cycles of the DPR test.

Comparative NOP PUD samples made with the same levels of NMP solvent (Sample D) as samples A, B, and C, the same formulations as Samples A and B, showed low ΔY values when untreated, but tested with aziridine crosslinkers. High ΔY values. For the latter sample, after 5 cycles of the DPR test, the change in white of the coated sample is clearly noticeable due to the black residue on the coating.

Commercial control samples E and F, made with 9 and 0% NMP solvents and made with additional 5% NMP solvents for flawless films, showed high ΔY values when untreated and were tested with aziridine crosslinkers. When higher ΔY values were shown. For both samples, in both cases, due to the black residue retained on the coating, the change in white of the coated sample was very significant after five cycles of the DPR test.

Commercial control samples E and F, made with 9 and 0% NMP solvents and made with additional 5% NMP solvents for flawless films, showed high ΔY values when untreated and were tested with aziridine crosslinkers. When higher ΔY values were shown. For both samples, in both cases, due to the black residue retained on the coating, the change in white of the coated sample was very significant after five cycles of the DPR test.

[Table 2A]

It is important to demonstrate that the change in solvent type from NMP to PROGLYDE ^® DMM has no negative effect on PUD coating properties due to natural oil polyols such as hydrophobicity. Place water droplets (covered with a watch plate to prevent evaporation) on the coated sample for a fixed period of time, dry the droplets from the surface, and any defects such as whitening, blushing, swelling, blistering Or by testing the coating for delaminating, thereby performing a water resistance test in accordance with ASTM D 870. The coating is dried at room temperature for 7 days before the experiment and contacted with water for 2 hours. Test results for the four NOP PUD samples shown in Table 3A show that water has a very small effect on the coating. These results confirm that the contribution of natural oil polyols to coating performance, such as water resistance, is preserved in PUD coatings and is independent of solvent selection.

[Table 3A]

The use of low-boiling solvents such as PROGLYDE ^® DMM (evaporation rate: 0.13 vs. nBuAc = 100) in place of high boiling solvents such as NMP (evaporation rate: 0.03 vs. nBuAc = 100) leads to faster volatilization of the solvent from the coating. Due to this, it is expected to improve characteristic expression (eg, early water resistance, hardness development, etc.) during curing. However, solvent selection is not expected to affect the final performance attributes of the cured coating, for example adhesion, dirt contamination resistance. The improvement of performance characteristics through the use of mild solvents is unexpected, which forms the basis of the present invention.

Since the present invention can be embodied in other forms without departing from the spirit and essential attributes thereof, it is intended to refer to the appended claims rather than to the foregoing specification, as indicating the scope of the invention.

Claims (4)

At least one polyurethane unit derived from at least one prepolymer comprising a reaction product of at least one natural oil-based polyol and at least one isocyanate dissolved in dipropylene glycol dimethyl ether in the presence of at least one surfactant and
Polyurethane dispersions comprising water. At least one prepolymer comprising a reaction product of at least one natural oil-based polyol and at least one isocyanate dissolved in dipropylene glycol dimethyl ether in the presence of at least one surfactant and optionally neutralized with at least one neutralizing agent Providing a first stream comprising:
Providing a second stream comprising water,
Joining the first stream and the second stream together,
Thereby forming a prepolymer dispersion,
Optionally neutralizing the prepolymer dispersion,
Chain extending the prepolymer,
Thereby forming a polyurethane dispersion
A method of producing a polyurethane dispersion comprising a. Board,
A coating associated with one or more surfaces of the substrate
And the coating is
At least one polyurethane unit derived from at least one prepolymer comprising a reaction product of at least one natural oil-based polyol and at least one isocyanate dissolved in dipropylene glycol dimethyl ether in the presence of at least one surfactant and
water
A coated article derived from a polyurethane dispersion comprising a. Selecting a substrate,
At least one polyurethane unit and water derived from at least one prepolymer comprising a reaction product of at least one natural oil-based polyol and at least one isocyanate dissolved in dipropylene glycol dimethyl ether in the presence of at least one surfactant Selecting a coating composition comprising a polyurethane dispersion comprising
Applying the coating composition to at least one surface of the substrate,
Removing at least a portion of the water,
Thereby forming a coated article
Comprising a method of making a coated article.

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